My boyfriend and I stayed at Onladas for 1 month. We enjoyed staying there although the apartment felt quiet small for a whole months stay. It was very clean, equipped with basic kitchen utensils, and central.
Onlada was an amazing host. We arrived later than expected yet she waited patiently for us, to show us the room and hand us the keys. When there was an issue, she responded promptly and had it fixed within 10 minutes.
The best part of the building is definitely the amenities. Nice pool with a lounging area and a great gym. You get full sun until the sun goes down.
The location of the apartment is about a 15 minute walk to the BTS Onnut. There's a big C (grocery store) around the corner which is great for grocery shopping. There's a mall across the street from the building that has a variety of restaurants and a 24/7 7 eleven.
All in all great place for your time in Bangkok!